Switch.



V. H. CA'RMAN.

SWITCH.

APPLICATION FILED DE0.11, 1912.

Patented Aug. 5, 1913.

. illu UNIIIIED STATES PATENT OFFICE.

VICTOR H. CARMAN, OF INDIANAPOLIS, INDIANA, ASSIGNOR T0 CARIVIAN @c FRYER,

A COPAR-TNERSI-IIP COMPOSED 0F HIIVISELF AND DAVID L. FRYER, OF INDIAN- APOLIS, INDIANA.

SWITCH.

Specification of Letters Patent.

Patented Aug. 5,1913.

To all whom t may concern.'

13e it known that I, VICTOR H. CARMAN, a citizen of the United States, residing at Indianapolis, inI the county of Marion and State of Indiana, have invented a new and useful Switch, of which the following is a specification.

.In electrical work, it is frequently desirable to change the connections of certain coils from series to parallel, or from star t0 delta, and vice versa, as well as to cut such coils entirely out of circuit. For instance, in starting three phase induction motors, it is advantageous first to connect the primary windings of the motor to the supply line in star, thus reducing the impressed voltage per turn at starting, and to change the connections to delta, to raise the impressed voltage per turn, after the motor has gained speed.

It is the object of my invention to provide a simple switch, or the knife blade type, for accomplishing this. To this end I provide a plural-bladed switch, each blade of which cooperates with two contacts, engaging one Contact before it engages the other but remaining in Contact with the first when in contact with the second. In addition, there are auxiliary contacts movable with the switch blades and connecting` together the contacts last engaged by the switch blades when the latter are in engagement only with the contacts first engaged thereby. Each of the contacts lirst engaged by the switch blades is connected to one end of one of the coils or windings to be controlled, the other ends of said. coils or windings being connected to non-corresponding contacts of those last engaged by the switch blades. Then these coils ai'e of a polyphase set, as the windings of a three phase induction motor, the two contacts cooperating with any switch blade are connected respectively to those ends of adjacent coils of the set which would be connected together when the coils are in delta.

The accompanying drawings illustrate my invention.

Figure 1 is a perspective 'view of a switch embodying my invention, the switch being shown open in full lines, and completely closed, in `position for delta connection, in dotted lines; Fig. 2 is a side elevation of this switch, one of the switch blades being partly broken away to show the auxiliary switch blade contact and insulation behind it, the switch here being in its first closed, or at star-connecting, position; and Figs. 3 and 4 are diagrams showing the connections produced by the switch in its first and its final closed positions, respectively.

On the base 10, of insulation, are mounted a plurality of pivotal supports 11, 12, and 13, to which are pivoted the switch blades 14, 15, and 1G. The outer ends of these switch blades are suitably fastened to a cross bar 17 of insulation, whereby they can be moved together by a common operating handle 13. he knife blades coperate with two sets of contacts 19, 20, and 21, and 22, 23, and 24. The contacts 19, 20, and 21 are longer than the contacts 22, 23, and 24, so that they are engaged by the respective knife blades before the latter contacts are, but remain in engagement with the knife blades after the latter contacts have been engaged thereby, as indicated in Fig. 2 and in dotted lines in Fig. 1, respectively. The contacts 22, 23, and 24 are provided with auxiliary contacts 22, 23 and 23 and 24, respectively, these auxiliary contacts, which are conveniently though not necessarily separate pieces from the main contacts, extending upward and toward the auxiliary contacts of the adjacent main contacts, as shown in Fig. 1, so that auxiliary switch blade contacts 25 and 26, carried by blocks 27 and 28 of insulation suitably mounted on the cross bar 17, may pass between and engage the contacts 22 and 23, and 23 and 24, respectively, when the switch has been brought to its rst closed position, as indicated in Fig. 2. rlhe contacts 19, 20, and 21 are connected to the corresponding ends (the clockwise ends as illustrated) of coilsl 30, 31, and 32, respectively. The contacts 22, 23, and 24 are connected to the other (or counter clockwise) ends of the coils 31, 32, and 30, respectively. rInus the two ends of each of said coils are connected to non-coi'responding contacts of the two sets. The coils 30, 31, and 32 are illustrated as the primary windings of a three-phase induction motor 33, but may be any other coils which it is desired to control in a similar manner.

Then the switch is open, as shown in full lines in Fig. 1, the coils 30, 31, and 32 are entirely disconnected. As the switch is moved to closed position, the switch blades 14, 15, and 1G first engage the contacts 19, 20, and 21, thus connecting one end of each of the coils 30, 31, and 32 to one of the wires of the three-phase supply system 35, 36, and 3T, which three wires are suitably connected to `the switch blade supports 11 12, and 13. At substantially the same time, the auxiliary switch blade contacts 25 and 26 engage the auxiliary contacts 22 and 23, and 23 and 24, respectively, thereby connecting together the other ends of said three windings 30, 31, and 32. This connects these three windings in star, making it. necessary for the current to pass in series through two of such windings in order to go from one of the supply mains to another. As a result, each of the windings 30, 31, and 32 has impressed thereon less than the full voltage of the supply line. when the motor has gained speed, or at any other desired point in the operation in case the windings 30, 31, and 32 are not motor windings, the handle 1S is pushed completely down, to bring the switch to the position shown in dotted lines in F ig. 1. ln this position the connections between the switch blade supports 11, 12, and 13 and the switch contacts 19, 20, and 21 are maintained, and are extended to the contacts 22, 23, and 2e, respectively; while slightly prior to the engagement of the switch blades with the contacts 22, 23, and 24, the auxiliary switch blade contacts 25 and 26 pass out of engagement with the auxiliary contacts 22', 23', 23", and 2st, and their places are taken by the blocks of insulation 27 and 28 to prevent arcing from one auxiliary contact to another. lith the switch in the final closed position, as shown in dotted lines in Fig. 1, the windings 30, 31, and 32 are connected in delta, as shown in F ig. 4;. The current may now pass from any one of the supply mains to another through two paths, one of which comprises but one of the windings 30, 31, and 32 while the other comprises the other two windings in shunt thereto but in series with each other. The full voltage of the supply circuit is now impressed on each of the windings 30, 31, and 32.

I claim as my invention:

1. A knife blade switch, comprising a plurality of pivoted knife blades, two sets of contacts with which said knife blades cooperate, each of said sets comprising a contact for each knife blade and the contacts of one set being engaged by the knife blades both prior to and at the time the contacts of the other set are so engaged, and auxiliary contacts which connect together the contacts of the second set when the knife blades are in engagement with the first set only, in combination with a plurality of coils one end of each of which is connected to a contact of the first set of contacts and the other end of each of which is connected to a noncorresponding contact of the second set of contacts.

2. A knife blade switch, comprising a I plurality of pivoted knife blades, two sets l of contacts with which said knife blades cooperate, each of said sets comprising a contact for each knife blade and the contacts of one set being engaged by the knife blades both prior to and at the time the contacts of the other sets are so engaged, and auxiliary contacts which connect. together the contacts of the second set when the knife blades are in engagement with the first se only.

3. A polyphase knife switch, comprising more than two piroted knife blades, two sets of contacts which are engaged successively by the knife blades as the switch is closed, each set comprising one contact for each knife blade, the contacts which are first engaged by the knife blades remaining in contact therewith while the contacts of the second set are in engagement with the knife blades, auxiliary knife blade contacts movable with the knife blades, auxiliary contacts connected with the contacts of the second set and engaged by said auxiliary knife blade contacts to connect together the contacts of the second set when the knife blades are in engagement with the contacts of the first set only, and blocks of insulation associated with the auxiliary knife blade contacts so that when the knife blades are in engagement with the contacts of both sets said blocks of insulation are located be- .tween the auxiliary contacts to prevent arcing, in combination with polyphase windings one end of each of which is connected to a contact of the first set and the other end of each of which is connected to noncorresponding contactof the second set.

1l. A polyphase knife switch, comprising more than two pivoted knife blades, two sets of contacts which are engaged successively by the knife blades as the switch is closed, each set comprising one contact for each knife blade, the contacts which are first engaged by the knive blades remaining in contact therewith while the contacts of the second set are in engagement with the knife blades, auxiliary contacts movable with the knife blades, and other auxiliary contacts connected with the contacts of the second set and engaged by the first-named auxiliary co-ntacts to connect together the contacts of the second set when the knife blades are in engagement with the contacts of the first set only, in combination with polyphase windings one end of each of which is connected to a contact of the first set and the other end of each of which is connected to a non-corresponding contact of the second.

5. A switch, comprising more than two contact members, two sets of contacts, which are engaged successively by the contact members as the switch is closed, each set comprising one contact for each contact member, the contacts which are first engaged by the contact members remaining in contact therewith while the contacts ofthe second set are in engagement with the contact members, auxiliary blade contacts movable with the contact members, auxiliary contacts connected with the contacts of the second set and engaged by said auxiliary blade contacts to connect together the contacts o-f the second set when the contact members are in engagement with the contacts of the first set only, and blocks of insulation associated with the auxiliary blade contacts so that when the contact members are in engagement with the contacts of both sets said blocks of insulation are located between the auxiliary contacts to prevent arcing.

6. A switch, comprising more than two contact members, two sets of contacts which are engaged successively by the contact members as the switch is closed, each set comprising one contact for each contact member, the contacts which are first engaged b y the contact members remaining in contact therewith while the contacts of the second set are in engagement with the contact members and auxiliary contacts movable with the contact members to connect together the contacts or the second set when the contact members are in engagement with the contacts of thel first set only.

7. The combination of a plurality of coils, supply conductors and a knife blade switch connected to both said coils and said conductors, said switch having open, intermediate, and closed positions and when in the intermediate position connecting said coils in series across said supply conductors and when in closed posit-ion connecting said coils in parallel paths across said supply conductors, switch blades included in the series connection being also included in the parallel connection.

S. The combination of polyphase windings, a polyphase supply circuit, and a knife blade switch which is connected to both said windings and said supply circuit and which in one position connects said windings tosaid supply circuit in delta, in another position connects said winding to said supply circuit in star, and in a third position disconnects said windings from said supply circuit, the position of the switch wherein the windings are connected in star being an intermediate position between the other two positions.

9. The combination of polyphase windings, a polyphase supply circuit, and a knife blade switch which is connected independently to both the windings and the supply circuit and has a plurality of sets of contacts each comprising a number of contacts equal to the number of phases and a number of knife blades equal in number to the number of phases for interconnect-ing corresponding contacts of the different sets, which switch in one position connects said windings to said supply circuit in stai', in another position connects said windings to said supply circuitin delta, and in a third position completely disconnects said windings from said supply circuit.

l0. The combination of polyphase windings, a polyphase supply circuit, and a switch which is connected independently to both the windings and the supply circuit and has a plurality of sets of contacts each having a number of contacts equal to the number of phases and a plurality of movable members equal in number to the number of phases, which switch in one position connects said windings to said supply circuit in star and in another position connects said windings to said supply circuit in delta.

11. The combination of polyphase windings, a polyphase supply circuit, and a knife blade switch which in one position connects said windii'igs to said polyphase supply circuit in delta, in another position connects said windings to said supply circuit in stai', and in a third position disconnects said windings from said supply circuit, the position of the switch wherein the windings are connected in star being an intermediate position between the other two positions, said switch having a contact for connection to each end of each of said windings and a contact for connection to each of the polyphase supply conductors.

12. The combination of polyphase windings, a polyphase supply circuit, and a knife blade switch which in one position connects said windings to said polyphase supply circuit in star, in another position connects said windings to said supply circuit in delta, and in a third position disconnects said windings from said supply circuit, said switch having a contact for connection to each end of each of said windings and a contact for connection to each of the polyphase supply conductors.

13. The combination of polyphase windings, a polyphase supply circuit, and a knife blade switch which in one position connects said windings to said polyphase supply circuit in star and in another position connects said windings to said supply circuit in delta, said switch having a contact for connection to each end of each of said windings and a contact for connection to each of the polyphase supply conductors.

14. A knife switch, comprising a plurality of sets of contacts, and a plurality of knife blades movable to an open position and two closed positions in one of which closed positions corresponding contacts of the different sets are connected together and in another of which closed positions the contacts of one set are all connected together and the knife blades engage corresponding contacts of another set, the last mentioned closed position being' an intermediate one between the open positions and the other closed position.

15. A knife switch, comprising a plurality of sets of contacts, and a plurality of knife biades movable to two closed positions in one of which closed positions corresponding contacts of the different sets are connected together and in another of which closed positions the contacts of one set are all connected together and the knife blades engage corresponding contacts of another set, the last mentioned closed position being an intermediate one between the open position and the other closed position.

16. A knife switch, comprising a plurality of sets of contacts, and a plurality of knife blades movable to an open position and two closed positions in one of which contacts of the diiiierent sets are connected together and in another of which closed positions the contacts of one set are all connected together and the knife blades engage corresponding contacts of another set.

17. A knife switch, comprising a plurality of sets of contacts, and a plurality of knife blades movable to two closed positions in one of which closed positions corresponding contacts of the diiferent sets are connected together and in another of which closed positions the contacts of one set are all connected together and the knife blades engage corresponding contacts of another set.

18. A switch, comprising a plurality of sets of contacts, and a plurality of bridging members, said bridging members being movable relatively to said contacts to two closed and an open position and in one closed position connecting corresponding contacts of three sets and in the other closed position connecting all the contacts of one set and also connecting corresponding contacts of two other sets, said latter closed position being between the former closed position and the open position.

19. A switch, comprising a plurality of sets of. contacts, and a plurality of bridging members, said bridging members being movable relatively to said contacts to two closed and an open position and in one closed position connecting corresponding contacts of three sets and in the other closed position connecting all the contacts of one set and also connecting corresponding contacts of two other sets.

20. The combination of a plurality of coils, supply conductors, and a switch having a plurality of movable members and connected to both said coils and said conductors, said switch having open, intermediate, and closed positions and when in the intermediate position connecting said coils in series across said supply conductors and when in closed position connecting said coils in parallel paths across said supply conductors, movable members of said switch which are included in the series connection being also included in the parallel connection.

In witness whereof, I have hereunto set my hand and seal at Indianapolis, Indiana, this fifth day of December, A. D. one thousand nine hundred and twelve.

VICTOR H. CARMAN. lVitnesses G. B. SCHLEY, MAY LAYDEN.

Oopies of this patent may be obtained for ve cents each, by addressing the Commissioner of Patents.. Washington, D. C. 

